Level gauge



FIG. 1 is a perspective view of the level gauge;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear elevational view thereof.

FIG. 4 is a front elevational view thereof;

FIG. 5 is a left side elevation of the level gauge, the right side is a mirror image of the left side; and,

FIG. 6 is a bottom plan view thereof; 

What is claimed is the ornamental design for a level gauge, as shown and described. 